Tamperproof covers are used on containers, particularly aerosol containers, to prevent prospective customers, especially customers in self-service stores from opening the containers prior to purchase. Many different types of tamperproof containers have been used. For example, Edelstone et al., U.S. Pat. No. 3,149,745, shows a double shell cover having an inner sleeve 26 with a locking ring 28 at the lower end thereof. The locking ring fits over and attaches to an undersurface 21 of a mounting cup 20 formed on the aerosol container. The locking ring 28 is split and can be released from engagement with the undersurface 21 by the use of a key, a screwdriver or other elongated implement inserted through an opening 31 in the outer sleeve. The elongated object engages and spreads lugs 30 located on opposite sides of the split in the inner sleeve. A seal 32 fits over the opening 31 in the outer sleeve of the cover. Since this cover can be opened by a key, an item normally carried by a prospective purchaser, it can easily be opened before purchase even though tampering with the seal 32 will be apparent. Further, there is a danger of puncturing the domed top of the aerosol container if a key, screwdriver or other elongated implement is inserted through the opening 31 in the outer sleeve of the cover.
Gach U.S. Pat. Nos. 3,515,307 and 3,532,249 also show tamperproof covers which, for removal, require the insertion of a screwdriver or other elongated implement through an opening in the outer wall of a double-wall cap with the tip of the screwdriver contacting the dome of the aerosol can and used as a lever. These covers include inner sleeves with locking flanges. Ribs connect the inner and outer sleeves. The use of a screwdriver or other elongated implement in the manner taught by these patents can lead to puncturing of the aerosol container and all of the adverse consequences attendant thereto.
Gach U.S. Pat. No. 3,334,769, shows a tamperproof cover of the single sleeve type in which a lifting pad is located on the outer surface of the cover. This cover relies on a locking means carried by the cover which fits in a groove 24 below the mounting cup of the aerosol container.
A destructible non-replaceable tamperproof cover is shown in Vollers U.S. Pat. No. 3,460,708. This cover has a segmented inner sleeve 22 with each segment having an inwardly projecting lip 24 which engages the undersurface of the mounting cup 14 of the aerosol container. To remove this cover, a screwdriver or other prying instrument is inserted through a notch 25 in the outer wall of the cap. Upon prying, one or more of the segments 22 of the inner sleeve will fracture. This cover is not being replaceable. It also requires the insertion of a screwdriver or prying device into the cover where it may puncture the dome of the aerosol container.
Many of the disadvantages of the above described tamperproof aerosol covers were overcome by the aerosol cover described in Richard H. Bennett U.S. Pat. No. 3,870,187, assigned to the assignee of this invention. The Bennett cover is a double sleeve cover with the sleeves connected by spaced ribs or webs 11. In the embodiment of the invention, shown in FIGS. 1 to 3 of the Bennett patent, the cover must be removed from the container through the use of a screwdriver, key or coin inserted between the outer rim 3 of the aerosol container and the circumferential flange 13 formed on the outer sleeve 9 of the cover. The skirt portion 14 of the outer sleeve extending below the flange 13 protects the domed portion 5 of the aerosol container against puncture by the screwdriver, key or coin. The cover of the embodiment of FIGS. 1 through 3 of the Bennett patent presented some problems in fit since the locking flange 12 was not easily adjustable to compensate for variances in the diameters of the mounting cups of aerosol containers. The adjustment problem was solved by the provision of a slit 15 in the inner sleeve of the cover as shown in the embodiment of FIG. 4 of the Bennett patent. Variations in the length of the slit will vary the tightness of the fit of the locking flange without requiring changes in the amount of undercut of the locking flange. The combination of ribs and a slit also permitted the cover of the Bennett patent to be used as a child resistant cover which could be removed by squeezing pressure applied to the outer wall of the cover combined with a concurrent upward or withdrawal action. However, this reduces somewhat the effectiveness of this cover as a tamperproof cover.
An object of this invention is to provide a tamperproof cover which functions as a child resistant cover when it is reinstalled on a container after its initial removal.
Another object of this invention is to provide a tamperproof cover which can be easily mounted on containers having mounting cups of slightly varying dimensions while still providing a tamperproof cover which cannot originally be removed solely by squeezing and manual manipulation of the cover.
Another object of this invention is a tamperproof cover which protects the container from accidental puncturing by the removal implement.
Another object is a tamperproof cover which is difficult, if not impossible, to remove with a coin or key in which requires an implement of the size and length of a screwdriver.